The present disclosure relates to systems and methods for treating subterranean formations.
Natural resources such as gas, oil, and water residing in a subterranean formation or zone are usually recovered by drilling a wellbore down to the subterranean formation while circulating a drilling fluid in the wellbore. After terminating the circulation of the drilling fluid, a string of pipe, e.g., casing, is run in the wellbore and cemented into place. Thereafter, one or more treatments may be performed in the subterranean formation and/or the well bore to facilitate the production of hydrocarbons such as gas and oil from the well, such as enhanced oil recovery operations, stimulation treatments (e.g., hydraulic fracturing), and the like. For example, an enhanced oil recovery operation is a generic term for techniques for increasing the amount of crude oil that can be extracted from a hydrocarbon-producing formation (e.g., hydrocarbon reservoirs). Such operations can be particularly useful in unconventional reservoirs (e.g., shale) where the extraction of such hydrocarbons may not be facilitated by natural buoyant forces.
In order to accomplish these treatments more effectively, one or more surfactants or emulsifiers may be injected into the formation, among other reasons, to lower the interfacial tension between oil and water which allows stable emulsions with small drops to be formed that can be carried out of the formation with the fluid. Conventional selection for selecting a surfactant typically focuses on one or two attributes of the surfactant. In particular for unconventional oil and gas plays, efficacy of the surfactant chosen for hydraulic fracturing may depend on a number of factors, including formation characteristics, oil types, reservoir temperature, and the other elements of the fracturing fluid. In some instances, a screening process comprising a set of experimental tests evaluating dynamic surface tension, interfacial surface tension, oil recovery tests, and/or wettability/imbibition tests has be used to evaluate surfactant performance for use in unconventional reservoirs prior to their use to identify surfactants that are more likely to maximize production and reduce risk of formation damage. However, these screening processes can be lengthy and tedious when used to screen large numbers of potential surfactants for use in a particular formation.
While embodiments of this disclosure have been depicted, such embodiments do not imply a limitation on the disclosure, and no such limitation should be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and not exhaustive of the scope of the disclosure.